Electric speedometer



May s, 1923. 1,454,644

C. F. KETTEFIING ELECTRIC SPEEDOMETER Filed Aug. 28 15918L 5 Sheets-Sheet l mmm, W

May s, 1923. f 1,454,644 C. F. KETTERING ELECTRI C SPEEDOMETER Filed Aug. 28 1918 3 Sheets-Sheet 2 Patented. may d, i

UNITED srares earner oFFici-i.

CHARLIE-SF. KETTERING, 0F DFYTON, Oli-EIC, ASSE-GHOR TG THE DAYTGN ENGENEERING LABORATORES COMPANY, CORPORATION OF OHIO.

nrincritic siennnoiliiernn.

Application filed August 28, 1918. Serial No. 251,755.

To all whom t may concern: y

Be it known that' l, CHARLES F. Kn'r'risn- ING, a citizen of the United States of America, residing at Dayton, county of Montgomery, State of Ohio, have invented certain new and useful improvements in Electric Speedometers, of which the following is a full, clear, and exact description.

This invention relates to speedonieters for vehicles and the like and has for one of its objects the provision of a speedometer which is very sensitive to slight changes in speed and very reliable and accurate in operation.

'More particularly it is an object of this invention to accomplish the purpose referred to by providing a speedometer in which the motion, which is imparted to the indicating member, is derived from a prime mover which is independent of the vehicle, instead of beingdriven directly by the vehicle itself, the quantity of motion which is delivered to the indicatin device being determined by auxiliary devices which are controlled by the speed of the vehicle.

Other and further objects of the present invention will be apparent from the following description thereof, reference being made to the accompanying drawings, in which preferred embodiments of the invention are shown.

ln thc drawings:

Fig. 1 is a plan view of one form of the i invention;

gear included in this form of the invention; Fig. 6 is a side view of an electro-magnet.

controllin device included in the form of the invention 'shown in Fig. 4. Fig. 7 is a plan View of the upper escapement member of the form of the invention shown in Figs. 1 and 2;.

Fig. 8 is an edge View thereof, partly in section; f

l Fig. 9 isla side elevation of the spring yieldingly connecting the upper and lower escapement members;

Fig. 10 is a plan view thereof;

Fig. 11 is a plan View of the lower escapement member included in the form of the invention shown in Fig. 1;

Fig. 12 is an edge view thereof partly in section;

n Fig. is a plan view of the energy storing spring;

Fig. 14 is a side view thereof;

Fig. 15 is a plan view of the resistor included iii the form of the invention shown in Fig. l;

Fig. 16 is a plan view of the collector disk included in the first form of the invention;

Fig. 17 is a side view thereof;

Fig. 18 is a top plan view partly in section of the indicator;-

Fig. 19 is'a side view thereof partly in section;

Fig. 20 is a plan view of the upper escapement wheel included in the second forni of the invention shown in Fig. l.;

Fig. 21 is an edge view thereof; ig. '22 is a plan view of the lower escapement member included in the second form of the invention;

Fig. 23 is a side view thereof;

Fig. 24 is a top plan View of the hunting topth rotating gear hub;

Fig. 25 is a side view thereof; and

Fig. 26 is a top plan view of the resistor included in the second form of the invention.

Referring to Fig. 3 which shows diagrammatically the first form of the invention shown in detail in Figs.` 1 and 2, it will he seen that this form" of the inventionv comprises in chief an indicating member 40 which depends for its action upon the motion transmitted to it from a prime mover which in this form is a series motor. In

.of the motor 50.

order to control the quantity ot motion-delivered to the indicator' hy the motor, the Speed ot the motor itsclt controlled by means ol' a rheostat 70, and the devices indicated at n0 in Fig. 3 constitute provisions dependent upon the speed oi' the engine lor actuating the rheostat so that the speed of the motor may be controlled in accordance with the speed of the engine.

Referring to Figs. l. 2, and d and Figs. 7 to i9 ot the drawings, the indicator at) which is of the usual magnetic drag type, comprises a permanent magnet al mounted to rotate with the shat't l2 and to drag a'lfter it the index member sl which is mounted by means oll pivot Din LH between the upper end of the shaft and a` screw 4:3 carried by the bracket 4G. jl. spring 48 connected to the index 42% and 'to a pin s?) mounted on the bracket 4G. serves to resist the movement of the index 43, duc to the action ot magnet al. The bracket Llr6 rt ts upon a plate Lt7 whicu in turn supported by the frame 51 The traine is provided with pole pieces 52 and which are energized by the field windings 5st and 55.Y The, shaft 42 is journalled in the supporting plate 47 and in the.

Ymotor traine l and carries the motor arma- `plate Referring to Figs. 1G and 17, a collector disk 7i ot insulating material is mounted upon the gear G5 and carries a. collector ring 72 which is adapted to be engaged by 'a brush 115 mounted upon the plate Li7 or insulated therefrom. 'ing 79 is provided with an upstanding ear 733 for ay purpose to be described. The disk 'il is provided with a pin 741 adapted to be engaged by a spring to be described. (The solid black used in Fig. 16 to indicate that the member 7l is made of insulated material. is broken away merely for the purpose'of showing the plan view of the gear 65.)

Referring to Figs?, and l5 a resistor ring 7 5 o't insulating material is provided with aresistor 7G, and is mounted upon the collector disk 71. The end 77 of the 'resistor 7G is soldered or otherwise permanently secured to the upstanding ear'73, and connection is thereby made with the collector ring 72. y

The wiper 78 which cooperates with the resistor 7G is mounted upon the lowercss capement wheel 81 which is mounted on the stub shalt 66 above the collector disk 7l and resistor 7G. escaoemcnt wheel Sl 1s shown in detai in l-io .tl and l2. @aid wheel bl is Awovided with a downwardly projectino pin Si and upr-/ardly projecting pin olriind a small hole Si.

The uppcr escapcinent wheel 1%.? is mounted upon thc stub shaft GU above the lower cscapenicnt wheel. Referring to Figs. 7 and 8 the wheel F provided with a slotted hole'SG into which projects the pin 88 carried by fthe wheel al. The wheel 85 is provided with a. small hole 87.

Referring more particularly to lfigs. f) and lt). a tlat spiral spring is provided with upwardly pi'ojccaing end of) which litsl into the hole 57, and a downwardly projecting end 90 which lits into the hole 8l provided in wheel til. When the .apcment wheels 8l and tlf: and the spring tls are in assembled relation. the pin S23 will he yieldingly held against the r hand. cnd ot the slot 86 as viewed in Fi".

Referring to Figs. l and li 2, a coil spring ill is nrovided and to Fig.

. with an eye 92 which engages the pin 2 c. cd b v the escapement wheel S11 and with another eye 93 which engae'es tln` pin 7i carried by the collector disk 7l.

The parts which arey mounted on the stub shaft 6G are retained in po.- ition by means ot a nut 9i which is threaded upon the up per end of said shal't ou.

The plate 47 carries a post lo() upon which is pivotally mounted ai armature lOl which carries a pawl ltl? adapted to cooperate with the lower cscapcnicnt wheel til and a pawl 1023 ac pl/cd to cn ge with the upper escapemenz wheel rio. .in electro-magnet 10st is mounted on he plate Le." and is provided with a. poliI piece 1.05 arranged adjacent the armature lOl.. itspring lo@ connected tothe Ytraine i? and to the armature lOl serves to move the same away vlrom the pole. 1(7)5 when thtl magnet lOll; 1;= not energized.

Referring to Fig. 3 batterij l itl grounded at lll and connected by wire i12 with the field windings 5t and 55 of the motor 50. which are connected by wire l'l with brush 5,9. Brush G0 is connected b v wire lle with the brush ll which cooperates with the .collector ring TQ. The rheostat wiper 78 is grounded by wire titl. The battery HOis connected by wire ll7 with one terminal of the magnet loll'. the other terminal of which is connected by wire llR with contact member llt) which cooperates with contact member 1.20. 120 being grounded by wire 121. The contacts lll and 1Q() are'suitably mounted on the 'traine ot the vehicle and are adapted to bc closed intermittcntly by some moving` part ot the vehicle as a pin 129 mounted on the vehicle wheel 123.

The operation of the "form of the invention described is as follows: 1t will he assumed first, that the speed of the vehicle stopped.

has reached a maximum at which time the relation of the different elements of the speedometer will be as shown in Fig. 1,and the wiper '78 will be iin-,engagement with the rst turn onthe left-hand end of the resistoi'76' and then, .that the vehicle has The motor 50. will continue to rotate at its maximum speed and cause the rotation ofthe resistor 76 in a clock-wise direction as viewed in Fig. 1. This motion will continue until the last turn of the resistor 76 on the right-hand end thereof as viewed in-Fig.. 1 has passed under the wiper 78. When this occurs the motor circuit will be broken and themotor will stop.

rThis movement of theA motor will cause the spring 91, to be wound up, and energy will be stored therein to effect the movement of the wiper 78 relative to the resistor 76.

When the vehicle is set in motion the contacts 119 arid 120 will be intermittently closed. Each time the contacts are closed the magnet 104 willdbe energized causing the movement of the armature 101 in a clock-wise direction as viewed in Fig. 1. This movement of theA armature 101 will release the lower escapement wheel 81 and cause the pawl 103 to move into engagement with the upper escapement wheel 85. After the pawl 102 has been moved out of engagement withthe escapement wheel 81,:the wheel 81 will move in a clock-wise direction viewed in Fig-. 1, until the pin 83 moves to the left-hand end ofthe slot 86 asV viewed in Fig. 1 when' the movement of wheel 81 will cease. The angle of movement of wheel 81 'is equal to the angle between adjacent tooth centers.

When the contact 120 has been released by the pin 122 the magnetv 104 will be deenergized, and the spring 106 will restore the armature 101 to the position shown in Fic.

1 thereby causing the pawl 102 to engage t e ratchet wheel 81 and to cause the pawl 103 to be .moved out of engagement with the wheel 85. This movement of the armature will cause the upper escapement wheel to move under the action of the spring 88 until the right-hand end of the slot 86 as viewed in Fig. 1 will 'engage the pin 88 carried by the ratchet wheel 81. This cycle of movements of the armature 101 and the escapement wheels 81 and 85, caused b v the closing and opening of the contacts 119 these movements are occurring the motor is running all of the time tending to cut in resistance in the motor circuit, but a balance will be established between these two opposing forces resulting in the resistor and wiper moving in the4 same direction and at the same speed, and therefore with no relative move- -motor comprising a frame 151 including poles 152 and 153. A shaft 154 is j ournalled in the frame 151 and carries a motor armature 156- and commutator 157 with which cooperate the motor brushes 159 and 160 which are supported en the frame 151. Upon the upper end of the motor shaft 154 is mounted the indicator 40.

The shaft 154 is Provided with an eccentric 161 shown in Fig. 5, which cooperates with the hunting tooth oscillating gear 162. Gear 162 is provided with pins 168 which cooperate with holes 164 provided in the hunting tooth oscillating gear retaining plate 165 which is secured to the frame 151 by means of screws 166. Hunting, tooth rotating gear 167 is providedwith a hub 168 shown in Figs. 24 and 25 by means of which the gear 167 is journalled u on the shaft 154. The hub 168 is provide with a notch 169 for a purpose to be described. The gear 167 is provided` with a `collector ring '172,

associated with a brush 115 in a manner similar to the collectorv ring 72 of the first form. A resistor disk 175 carrying a resistor 176 is mounted upon the gear 167 but insulated therefrom, and one end of the resistor 176 is connected with the collector ring 172. The gear 167 carries a pin 1'77 which engages the eye 93 and the. spring 91 shown in Figs. 13 and 14.

Referring to Figs. 22 and 23 the lower escapement wheel 181 is provided with a pin 182 which engages the other eye 92 of the spring 91. The wheel 181'is provided with a wiper 178 which contacts with the re.

sistor 176. The hub of heel 181 is provided with a projection 179 which engages the notch 169 of the hub 168 of the hunt-ing tooth gear 167. Escapement wheel 181 is provided with an arcuate slot 183 which is adapted to be engaged by a pin 186 carried by the upper escapement. wheel 185. wheels 185 and 181 are loosely journalled upon the shaft 154 and a flat spiral spring 188 occupies the. space between adjacent faces of the escapement wheels 181 and 185 and has one end thereof connected with a notch 184 in the wheel 181, and the other end connected with the pin 186.

-The motor frame 151 carrying the parts The t described in the Vforegoing paragraphs is mounted upon a. bracket 190. A magnet trame 191 is mounted upon the bracket 190 and supports an electro-magnet 193` and a pivotally mounted armature 191 which carri'cs a pawl 195 which is adapted to' cooperate alternately with the escapement wheels 185 and 181. The spring 196 connected between the armature 191 and the trame 191 serves to yieldingly maintain the armature 194 in the position as shown in Fig. G. y

The electrical connections between the battery 110, the motor, rheostat electro-magnet and contacts 119 and 120 are the same as the connections between the corresponding elements ot the first form ot the invention as shown in llig. i

The operation ot' this form4 of the invention is as Follows: Assuming that the vehicle has come to rest with all ot the resistance in the motor circ-uit cut out., the motor will continue to .operate until, through the huntino' tooth eearino. motion is trans- Y mitted to the resistor 176 causing it to gradually lcut in resistance in the motor circuit until the resistor moves entirely 'from under the wiper 178 and the motor circuit is broken. iVhile this motion talresplace, the upper escapement wheel 185'will 'be held stationary by reason of the engagement therewith of the pawl 195. T he esca-pement wheel 181 will be held stationary under the yielding pressure of the spring 188. After the motor circuit has been broken the motor will continue to rota e, due to its momentum, and cause the huntingtootlrgear 167 to rotate until one end oi' the notch 169 ot the hub 188 contacts with the projection 17 9 of the wheel 181. Then this occurs the motor armature will be stopped under the yielding pressure of the spring 188. This operation of the motor will cause the winding up of the spring 91 as in the case of the first form ot' the invention,

. Whenever, due to the movement ot the ve hicle, causing contacts 119 and 120 to close,

the magnet `193 is energized, the armature 194 will be attracted and the pawl 195 will be caused to move downwardly', thereby releasing the upper cscapement wheel 185 and engaging the lower escapement wheel 181. `then this occurs the upper escapement- Awheel 185 will be actuated due to the act-ion of the spring 188 relative to the wheel 181. lhen the circuit through the magnet 193 is broken the spring 196 will cause the armature 1941 to return to the posit-ion shown in Fig. 6, at which time the pawl 195 will move y out ot' engagement with the escapement action oi the vehicle in cutting out lower end oi the slot 188 as viewed in Fig. i2, moves into engagement with the pin 186 carried by the upper wheel 185. 4Vlelie wheel 181 will then have travelled thc distance between adjacent tooth centers. The cloclo wise movement or the wheel is such as to cause the wiper 178 to cut resistance out ot' the motor circuit. :is in the iiist form of the invention the laster the vehicle operates the more frequently the electro-magnet 193 will operate the pawl 195 in order to release the escapement wheels 181 and 185, whereby to cut resistance outof the motor circuit. rllhe q sistance will be opposcdby the action of (he motor `tendingl to cut in resistance. vThen these op` posing forces reach aI balance no relative motion between the resistor 1T@ and the wiper 178 will occur, and the motor will operate at a speed corresponding to the speed oit the vehicle.

lVhile the Forms oll mechanisms herein shown and described constitute preferred forms o'tcmbodimen'ts oi' the invention. it her 'forms might be l scope oi? the to be understood that. or adopted, all coming; wit claims which follow:

1. ln a synchronizing s' m tor electric motors, the combination i i h a motor; oli a rheostat in the motor circuit including as elements, resistor and a wiper; meansV actua-ted by theopcration olY Jthe motor ter. l' to move the resi 'or reathJe-ly to I a spring which is wound up by the s, of the 1notor5` and means contro movable part with which the i be synchronized tor releasing` t e spring whereby the wiper will he moved under the action of the springrelati` 1v'o hc resie in order to counteract tic i named means, thereby 'ten hin tne i the nist to increase the amount of current delirercd lo the motor.

2. ln a synchroniziirgg s motors, the combination a motor; o l' a rheostat in the motor circuit including;i as elements a resistor and a viper: nl vans aotuated bythe operation ot the motor for moving one ol the rheostat elements relatively to the other tending to reduce the current delivcrytothc motor to a minimum; a spring adapted to bo wound up by the motion ot' the motor; and means controlled by the movable part with which the motor is to be synchronized ior releasing the spring by step by step motion controlled by the speed ol the said part 'tor moving one oli' thc rheostat elements relatively to the other in order to counteract the ell'ect oiAv the first named means. thereby tending to increase the amount ot current delivered to the motor.

8. ln a. synchronizing system lor electric motors, the combination with a motor; of a rheostat in the motor circuit inclncinea resistor and a wiper, means actuated by the operation ot the motor for moving there- 35 minimum; a spring connected to the Wiper relatively'to theresistor thereby cutting resistance out of the motor'circuit and tending to increase the amount of current dei resistor relatively to the Wiper tending to reduce the current delivered to themotor to a minimum; a spring connected tothe Wiper A and adapted to be Wound up by the motor;

an escapement `vvheel connected to the spring; a pavvl co-operating With the escapementl Wheel; and means controlled by the movable part with which the motor is to be synchronized for actuating the pawl torelease the spring and thereby cause the Wiper to move relatively to the resistor.4

5. In a synchronizing system for electric motors, the combination with a motor; of a rheostatinthe motor circuit including a resistor and a -Wiperg means actuated by the operation ofA the motor for moving the reslstor relatively to the wiper tending to reduce the current delivered to the' motor to a and adapted to be Wound up by the motor; an escapement Wheel connected to the spring; a' pa-Wl co-operating with the escapement Wheel; an electro-magnetic means controlled by the motion of the part with which the motor is to be synchronized for actuating the paWl. to release the spring and thereby cause the Wiper to move relatively to the resistor.

6. In a synchronizing system for electric motors, the combination with a motor; of a rheostat inthe motor circuit including a resistor andv a' Wiper; means actuated by the operation of the motor for moving the resistor relatively to the Wiper tending to renduce the current delivered to the motor to a minimum; a spring connected to the Wiper and adapted to be Wound up by the motor;

an escapement Wheel connected-to the spring; a pawl co-operating With the escapement Wheel; an electro-magnet for operating the pavvl; co-operating switchl contacts connected in the magnet circuit; and means 'carried by -a moving part with which the motor is to be synchronized for intermittently closing the contacts, whereby to intermittently release the spring and to cause the Wiper to move relatively to the resistor. 7. In a synchronizing system for electric motors, the combination with a motor; of a rheostat in the motor circuit including a resistor and a Wiper; means actuated by the Operation of the motor for moving the resistor relatively to the Wiper to reduce the current delivered to the motor to a minimum; a spring connected to the wiper and adapted to be Wound up by the motor; yieldably connected escapement Wheels connected with the spring, said escapement Wheels including co-operating stops for limiting the motion between the Wheels; pawls adapted to co-operate With the escapement Wheels; and means controlled by the movement of a part with which the motor is to be synchronized for operating the patvls whereby the pawls will alternately engage the escapement Wheels to release the spring, whereby the Wiper is moved relatively to the resistor in order to oppose the first named means and to tend to increase the amount of current delivered to the motor.

8. In a synchronizing system for electric motors, the combination with a motor; of a rheostat in the motor circuit including a resistor and a Wiper; means actuated by. the

operation of the motor for moving the resistor relatively to the Wiper to reduce the current delivered to the motor to a minimum; a spring connected to the Wiper and adapted to be Wound up by the motor; yieldably connected escapement Wheels in diferent planes connected with the spring, said escapement Wheels provided with co-operating stops for limiting the motion between the escapement Wheels; a pivotally mounted armature provided with pavvls located in the planes of the escapement Wheels, said paivls adapted to alternately engage the escapement Wheels; an electro-magnet for operating the armature in one direction; a spring co-operating with the armature for moving the same in the opposite direction; and

means controlled by the movement of a part with which the motor is to be synchronized for intermittently permitting current to flow to the magnet.

9. In a synchronizing system for electric motors, the combination with a mofor; of means operated by the motor tending to reduce the motion of the motor and to store energy in an energy storing device; means adapted to be actuated upon the release of the energy storing device and thereby tending to increase the motion of the motor; and means controlled by the movement of a part With which the motor is to be synchronized to eitect the release of the energy storing device.

lO. In a synchronizing system for electric motors, the combination with a motor; of a device for controlling the speed ot the motor including' a rstand a second member movable relatively to each other; means actuated continuously by the motor tending to move Jshe first member relatively to the second with the first mea-ns resulting in the estabwhereby *fo decrease he motion of the motor; lishment of :L xed relation between the first means independent ol 'driving` connection und second members Corresponding to the with n movable part with which the molo]- speed of said movable part.

5 is to be synchronized for causing the second In testimony whereof I aihx my signature. 15

member to tend to move relatvelv to 'the l 7 lq q 4 '4 T first member whereby to mereese motxon of Y CHJJD I" KnTrl ERIB G' the motor and means Controlled by smd movbhtnesses: able part perlodlcally to release sind second J. W. MoDoNALD,

10 means, `the Co-operation of said second means 4M. A. PEARE. 

